1. Field of the Invention
The present invention relates generally to fan apparatus, and more particularly relates to a side-vented axial fan and methods of fabricating it.
2. Description of Related Art
Small axial flow fans are typically used in a variety of cooling applications such as in various computer system components including computer housings, printer housings and monitor housings. Conventional axial fans of this type typically include a molded plastic housing through which the axial air flow opening extends, and an electric motor-driven bladed impeller centrally supported within the unitary housing structure.
In small axial cooling fans of this general type a recent design proposal has been made to lower the operating noise and increase the overall air flow rate of such fans by forming side inlet openings in the fan housing so that during fan operation air is drawn into the side inlet openings and flowed through the rotating impeller section together with the air flow axially entering the fan as conventionally constructed.
Under this recent design proposal a rectangular outlet side portion of the fan housing is provided with a spaced set of posts projecting outwardly therefrom in an upstream direction relative to the ultimate axial air flow through the housing. A plurality of rectangular plate members having central air flow openings and corner connection openings therein are provided together with a plurality of separate hollow cylindrical spacer members.
The post members are passed through the plate member corner openings and the separate spacer members in a manner such that the plate members are in a stacked, parallel array and mutually separated by the separate spacer members to define between the plate members the desired side inlet openings of the overall fan housing. To retain them on the post members the plate members and the separate spacer members are glued in place on the post members.
This has been found to be a rather tedious and time-consuming fabrication process and presents several other problems as well. For example, it has been found desirable from an aerodynamic standpoint to slope annular portions of the plate member, which circumscribe the central openings of the plate members, in a radially inward and downstream direction. This leads to the possibility of inadvertently installing one or more of the plate members in a reversed orientation on the post members.
Additionally, in some housing configurations side inlet openings of different widths have been investigated. This design undesirably necessitates the provision of differently configured separate spacer members, and also requires that the spacer members be installed on the post members in a predetermined sequence. If this sequence is not adhered to the designed for side inlet spacing configuration is not achieved.
From the foregoing it can readily be seen that it would be desirable to provide improved methods of fabricating a side-vented axial fan of the general type described above which eliminates or at least substantially reduces the problems, limitations and disadvantages associated with the described fabrication method. It is accordingly an object of the present invention to provide such improved methods together with a side-vented axial fan constructed thereby.